NASA has not disclosed Kopra’s injury, but Houston’s ABC News says two sources have confirmed he broke a hip. Chief astronaut Peggy Whitson, who visited Kopra at his home, says he expects a full recovery.

“But was he wearing a helmet??” some wags will invariably ask.

The dude is a rocket scientist — what do you think?

Actually, we don’t know what kind of helmet he was wearing, if any, but we’d like to think it was a space helmet.

Astronaut Stephen Bowen will take over Kopra’s spacewalking duties.

U.S. Army astronaut Col. Tim Kopra in an undated file photo provided by NASA. On Wednesday, Jan. 19, 2011, NASA removed Timothy Kopra from the crew and added veteran spaceman Stephen Bowen. Bowen flew on the most recent shuttle flight, last May. Bowen will assume Kopra’s spacewalking duties during the 11-day flight. That flight has been on hold since November because of fuel tank cracks.